Reinforced ceramic matrix composite articles (CMCs) are well suited for high temperature structural applications because of their toughness, thermal resistance, high temperature strength and chemical stability. To make a CMC article, fiber is initially shaped to create a porous preform, the porous preform is rigidized with a ceramic phase(s), and the porosity is filled with a ceramic slurry bonded by a molten alloy infiltrant.
For example, silicon carbide (SiC) matrix composites have been made by infiltrating a silicon carbide slurry into a porous fiber preform to form a green composite article. A molten alloy infiltrant material including silicon (Si) may then be introduced into the green composite article using capillary forces to densify the structure to less than about 5% porosity and form a CMC article.